arm64: dts: mediatek: mt8192: Add GPU nodes

arm64: dts: mediatek: mt8192: Add GPU nodes

The MediaTek MT8192 includes a Mali-G57 GPU supported in Panfrost. Add
the GPU node to the device tree to enable 3D acceleration.

The GPU node is disabled by default. It should be enabled by board with
its power supplies correctly assigned.

Signed-off-by: Alyssa Rosenzweig <alyssa.rosenzweig@collabora.com>
[nfraprado: removed sram supply, tweaked opp node name, adjusted commit message]
Signed-off-by: Nícolas F. R. A. Prado <nfraprado@collabora.com>
[wenst@: disable GPU by default; adjusted prefix; split out board change]
Signed-off-by: Chen-Yu Tsai <wenst@chromium.org>
[Angelo: cosmetic fixes]
Signed-off-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>
Reviewed-by: Chen-Yu Tsai <wenst@chromium.org>
Tested-by: Chen-Yu Tsai <wenst@chromium.org>
Link: https://lore.kernel.org/r/20230301095523.428461-8-angelogioacchino.delregno@collabora.com
Signed-off-by: Matthias Brugger <matthias.bgg@gmail.com>